Zoanthoxanthin, a heteroaromatic base from Parazoanthus cfr. axinellae(zoantharia): structure confirmation by X-ray crystallography

Metabolomic profiling reveals deep chemical divergence between two morphotypes of the zoanthid Parazoanthus axinellae

“…Their structure elucidation was based on combined NMR and MS data, and further comparison with literature data. Thus, the three main chemical families are: ecdysteroids including 20-hydroxyecdysone ( 1 ) 24 , 20-hydroxyecdysone 2-acetate ( 2 ), 20-hydroxyecdysone 3-acetate ( 3 ) 25 , and viticosterone E ( 4 ) 26 ; zoanthoxanthins including parazoanthoxanthins C ( 5 ) and D ( 6 ), norpseudoparazoanthoxanthin ( 7 ) 20 21 22 and paragracine ( 8 ) 27 ; and parazoanthines ( 9-16 ) ( Figure 2 ) 23 28 .…”

“…While 20-hydroxyecdysone ( 1 ) appears as the major compound in the “stocky” morphotype, the acetylated forms of 20-hydroxyecdysone 2 and 3 are the major ecdysteroids in the “slender” morphotype. On the contrary, the occurrence of parazoanthines 9 - 16 is intriguing since: i) they are the major secondary metabolites of the crude extracts of the “slender” morphotype, and they are never detected in the “stocky” morphotype; ii) as parazoanthines and zoanthoxanthins have similar polarities, the earlier chemical studies which reported the presence of zoanthoxanthins should have also identified parazoanthines if present ( Figures 6 ) 20 21 22 . The extraction conditions cannot explain the absence of these metabolites in the earlier studies since ours were very similar.…”

“…Relatively few chemical studies have been reported so far on P. axinellae although it is a widespread zoanthid, particularly in the Mediterranean Sea. In the 1970's, Cariello et al provided the first results describing some components of the secondary metabolome of this species 20 21 22 . They isolated and characterized several zoanthoxanthin derivatives.…”

“…The secondary metabolome of P. axinellae was first studied in the 1970s with the isolation and structure elucidation of polyaromatic alkaloids named zoanthoxanthins and parazoanthoxanthins 20 21 22 . Recently, a second original family of alkaloids, named parazoanthines, was recovered from the same species 23 .…”

Characterization of Parazoanthoxanthin A Binding to a Series of Natural and Synthetic Host DNA Duplexes

“…Parazoanthoxanthin A (Fig. 1A) is a yellow nitrogenous pigment from the group of zoanthoxanthins (2) that are produced in some colonial anthozoans of the order Zoantharia, e.g., Parazoanthus axinellae (3). Extensive chemical studies have shown that zoanthoxanthins are tetra-azacyclopentazulene compounds (4 -9).…”